Glass, sand, or flint paper, emery cloth, or like abrasive



Patented Oct. 9, 1928.

UNITED, sTA

cm ADOIJPHI KLEIN, or BBmsDowN, AND ROBERT SKIRVING nnowN, oF LoNDoN,

'. ENGLAND.

emss, SAND, on FLINT IPAIfER, EMERY CLOTH, on LIKE AnRAsIvE.

No Drawing. Application filed October 28, 1925, Serial No; 65,487, and in GreatiBritain-A ugust 26, 1925.

This invention relates to that class of glass, sand or flint paper, emery cloth or like abrasive, which is waterproof so thatit can be used on damp or wet surfaces without being affected by the moisture.

Various attempts have been made to prepare abrasive paper or other material of this class, but in all instances these prior processes involve in some way the use of a lead or similarly poisonous dryer, thus nullifying one of the most important properties of such waterproof papers, more particularly when used y- Now it hasbeen found that by the-use of the process described in the specification of our application for patent, Serial No. 65,486 of even date herewith a waterproof sand paper (01'' like abrasive) is obtained in which no lead or other poisonous material is employed, so that it can be used either on damp or wet surfaces without being injuriously affected by the moisture, or in a dry state without the risk of fine particles of its adhesive composition being disseminated in the atmosphere and prejudicially affecting the health of the user.

The present invention therefore consists a waterproof sheet abrasive material in the preparation of which no lead or other poisonous agent is employed.

The process described in the specification of the pending application for patent above referred to consists, as applied to the manufacture of waterproof sandpaper, in running a per forming the base from a reel, from WlllCll it passes (after if desired being printed on the back) into a bath of linseed oil which is kept at a temperature of at least 100 C. ,A small proportion (say about 0.5 per cent) 'ofparaffin or other suitable wax is added to the lin-' seed oil bath, to increase the waterproofing efiect.

From this bath the paper preferably passes between a pair of pressure'rollers to remove any surplus of the waterproofing material, and which are also kept heated to 100 C. or

over. 4

It may then be rewound intoreel form pass at once direct to a table or series of hot" plates or rollers kept at a temperatureof 100 C. or over and while passing over this table or series of hot plates or rollers the adhesive employed to secure the abrasive to the paper is applied in any. suitable manner. This adihesive, which consists of a mixture of a drying oil. (such as linseedoil or tung oil) with a gum (such as dammar or copal) or synthetic resin, is heated to over 100 C. and applied to the paper while at this temperature.

The following is an example of a suitable composition for this adhesive, viz: Parts by weight. Linseed or tung o1l 3 Dammar orcopal gum;

In the sequence of operations the paper thus waterproofed and coated with adhesive passes from the table, hot plates or rollers, and the sand (or other abrasive) is applied in any suitable manner. The paper is then baked at a temperature of over 100 C. Subsequently a second or sizing coating of adhesive is ap plied, according to common practice, after which the sheet abrasive is rebaked' (at a temperature of over 100 C.) and the paper will then be ready for use.

The process above described may be modified by the addition, to the adhesive composition above described, of a small pro ortion (for instance from 2 to 5 per cent) 0 paraffin or other suitable wax. In this case the paper, after passing from the table or hot plates or rollers where the adhesive is applied, is next chilled, after which the abrasive is applied. The paper thus coated passes between hot rollers to press the abrasive down into the warmed adhesive composition, after which it is baked at at least 100 C. as before, but the second or sizing coating of adhesive and the V workers from the inhalation of the vapors of such volatile thinners.

What we claim and'desire to secure by Letters Patent-is A v 1. 'A water roof sheet abrasive material comprising a ase, a waterproofing composition applied to such base as a preliminary treatment and consisting of linseed oil with a small proportionof parafiin wax, an adhesive composition subsequently applied and consisting of a drying oil with a gum, and an abrasive material.

'2. A waterproof sheet abrasive material comprising a base, a waterproofing composition applied to such base as a preliminary treatment and consisting of linseed oil with a small proportion of a suitable wax, an adhesive composition subsequently applied and consisting of a drying oil with a gum, and an abrasive material.

3. A waterproof sheet abrasive material comprising a base, .a waterproofing compositreatment and consisting of linseed oil with a small proportion of paraflin wax, an adhesive composition subsequently applied and consisting of a drying oil with a gum and a small proportion of paraflin wax, and an abrasive material.

5. A waterproof sheet abrasive material comprising a base, a waterproofing composition applied to such base as a preliminary treatment and consisting of linseed oil with a small proportion of a suitable wax, an adhesive composition subsequently applied and consisting of a drying oil with a gum and a small proportion of a suitable wax and an abrasive material, as specified.

6. Aiwaterproof sheet abrasive material comprising a base, a waterproofing composition applied td such base as a preliminary treatment and consisting of linseed oil with a small proportion of\paraflin wax, an ad hesive composition subsequently applied and consisting of a drying oil w ith a synthetic resin and a small proportionof a suitable wax, and an abrasive material.

7. A waterproof sheet abrasive*\ nateria l comprising a base, a waterproofing composition applied to such base as a preliminary treatment and consisting of linseed oil with a small proportion ,of a suitable-wax, an adhesive composition subsequently applied and consisting of a drying oil with a synthetic resin and a small proportion of a suitable wax, and an abrasive material.

In witness whereof we aflix our signatures.

CARL ADOLPHE KLEIN. ROBERT SKIRVING BROWN. 

